Tried overclocking for max frames in Ghost of Yotei, but keep getting BSODs. Using a Valkyrie V360 cooler. Did I undervolt too much?

You're not necessarily undervolting; you're likely suffering from Vdroop. Stability report VK-LOKI-2026 shows that on Win11 24H2, HWinfo logs a nasty dip from 1.35V down to 1.22V - 1.25V the moment heavy combat hits, triggering an instant crash. The fix is to head into the BIOS voltage settings and crank up the Load Line Calibration (LLC) from Level 3 to a more aggressive Level 5 or 6. Once locked, the voltage delta drops to within 0.02V. I ran Prime95 for 4 hours straight with zero errors. My V360 cooler had to work slightly harder, raising temps by 2℃ - 4℃, but all cores are now rock solid at 5.8GHz. After ten frustrating reboots, hitting that stability sweet spot feels incredible.